ACP Seminar (Astronomy - Cosmology - Particle Physics)

Speaker: Knud Jahnke (MPIA)
Title: Why do super-massive black holes accrete?
Date (JST): Wed, Oct 30, 2013, 16:00 - 17:30
Place: Seminar Room A
Related File: 1033.pdf
Abstract: Supermassive black holes in galaxies are interesting. On one side, their physics by itself is partially elusive and we simply want to understand how they form and grow. One the other side, their vast energy emission when accreting matter is so large that they could massively impact star formation in their hosting galaxy by affecting the gas reservoir. But what is the mechanism that drives gas into the central regions of a galaxy, around the black hole? Most of the gas' angular momentum has to be transported away, i.e. more than 99.999% of it.

I will review the known observational evidence for and against the main suspected mechanisms to transport gas from larger scales: galaxy collisions and secular, less violent effects. Which process dominates in which part of parameter space? Does this change with redshift and cosmic evolution? How limited is our knowledge. I will present the enormous advances that the field has experienced in recent years, and sketch our despite this still limited view on the fuelling mechanisms of AGN.